The thermal desorption spectroscopy measurements of He implanted silicon samples are reported. The He implantation energy was 90 keV (at 45° tilt) while the fluence was 10¹⁶ cm¯². Additionally, the influence of Si pre-implantation (fluences in the range 10¹⁴-10¹⁶ cm¯², E=260 keV) was under investigation. The He releases from both interstitials/vacancies (β peak) and cavities (α peak or rather band consisting probably of at least two peaks) were observed. The α peak disappears for the pre-implantation fluences larger than 10¹⁵ cm¯², while β peak becomes broader and shifts toward higher temperatures. The thermal desorption spectra were collected using heating ramp rates in the range 0.3-0.7 K/s. Desorption activation energy of the β peak for different pre-implantation fluences was found using the Redhead analysis of the β peak shift. It varies from 0.97 eV for the sample that was not pre-implanted up to 1.3 eV for the sample pre-implanted with the fluence 10¹⁶ cm¯².
The thermal desorption spectrometry studies of krypton implanted Si samples are presented. Implantations (with the fluence 2×10¹⁶ cm¯²) were done with the energies 100, 150, and 200 keV. Additionally, a 200 keV and 100 keV Kr⁺G double implantation was performed. A sudden Kr release was observed in the ≈1100-1400 K range, most probably coming from the gas bubbles in cavities. The desorption activation energy varies from 2.5 eV (100 keV) to 0.8 (200 keV). The peak splitting suggests existence of two kinds of cavities trapping the implanted noble gas. Two Kr releases are observed for the 200 and 100 keV double-implanted samples. The peak shift of the release corresponding to 100 keV implantation could be a result of both introduced disorder and higher effective Kr concentration. The desorption activation energy is risen to ≈3.2 eV for both releases.
Thermal desorption spectrometry measurements were performed for Ar implanted Si samples. Implantation energy E_{i} varied in the range 85-175 keV. The release of implanted Ar in two steps was observed in the temperature range 930-1300 K: the relatively narrow peak at lower temperature ( ≈ 930 K for implantation fluence 5 × 10^{16} cm^{-2}) is due to the release of Ar from the agglomerations (bubbles) while the broader peak observed for higher temperatures ( ≈ 950 K for implantation fluence 5 × 10^{16} cm^{-2}) comes from Ar atoms diffusing out of the sample. Inverse order of peaks is observed compared to the results for lower energy implantations (< 50 keV). Analyzing the thermal desorption spectra collected for different heating ramp rates enabled estimation of the desorption activation energy (2 eV for E_{i} = 85 keV and 1.7 eV for E_{i} = 115 keV).
For the first time the thermal desorption of H_2, N_2, O_2 and CO_2 is presented for antimony sulfoiodide (SbSI) xerogel made up of large quantity nanowires. The desorption has been observed near ferroelectric phase transition established at T_{c}=293.0(2) K. The Sievert measurements have shown that the hydrogen uptake is linear function of H_2 pressure (when p < 1.1×10^5 Pa). The hydrogen storage density in SbSI gel amounted 1.24× 10^{-2} wt% (for p = 1.08×10^5 Pa at room temperature).
Adsorption of Au on W(001) at 450 K up to multilayer structures was investigated. Temperature programmed desorption technique was used in determination of coverage dependent desorption energy (region up to one monolayer). Results were discussed in terms of competitive interactions of Au-Au and Au-W atoms. Simple procedure for prediction of faceting behavior on the interface, basing on the desorption data, was postulated. It was deduced that the Au/W(001) interface should not show faceting tendency after thermal treatment.
Various commercial and industrial properties of polymeric materials can be developed by the way of purposeful synthesis. For example, there are polymeric materials of extremely developed intrinsic microporosity. In attempts to further develop membrane properties (permeability and selectivity), the researchers artificially increase the pore sizes by various external influences, such as plastification by saturation of polymers with gases, sometimes in supercritical state, filling of a polymer with some non-organic components (zeolites). Sometimes, porosity of the composition appears to become higher than that of the components. This porosity, in difference with intrinsic one, can be called externally affected. The reason of these phenomena is not always clear, and in order to get some ideas in this field we suggest an experimental study using a combination of the two genetically interconnected (by spur processes) methods: positron annihilation lifetime spectroscopy and thermostimulated luminescence. This paper summarizes recently published and completely new results of the authors in order to illustrate the benefits of this experimental approach.
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